Due to changes in Slack’s API rate-limiting policies, API-based migration jobs are restricted to migrating only 15 messages per minute. This will significantly slow down the migration process when using an online workspace connection.
To avoid these delays, we recommend using our Import Tool, which lets you upload an exported Slack chat history file and does not rely on Slack APIs. If you must use the API method, consider contacting Slack support to request a rate limit exception for our migration app. Learn more about
Slack’s API rate limits.